• 제목/요약/키워드: Concurrent operation

검색결과 129건 처리시간 0.024초

2D Mesh SIMD 구조에서의 병렬 행렬 곱셈의 수치적 성능 분석 (An Analytical Evaluation of 2D Mesh-connected SIMD Architecture for Parallel Matrix Multiplication)

  • 김정길
    • 정보통신설비학회논문지
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    • 제10권1호
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    • pp.7-13
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    • 2011
  • Matrix multiplication is a fundamental operation of linear algebra and arises in many areas of science and engineering. This paper introduces an efficient parallel matrix multiplication scheme on N ${\times}$ N mesh-connected SIMD array processor, called multiple hierarchical SIMD architecture (HMSA). The architectural characteristic of HMSA is the hierarchically structured control units which consist of a global control unit, N local control units configured diagonally, and $N^2$ processing elements (PEs) arranged in an N ${\times}$ N array. PEs are communicating through local buses connecting four adjacent neighbor PEs in mesh-torus networks and global buses running across the rows and columns called horizontal buses and vertical buses, respectively. This architecture enables HMSA to have the features of diagonally indexed concurrent broadcast and the accessibility to either rows (row control mode) or columns (column control mode) of 2D array PEs alternately. An algorithmic mapping method is used for performance evaluation by mapping matrix multiplication on the proposed architecture. The asymptotic time complexities of them are evaluated and the result shows that paralle matrix multiplication on HMSA can provide significant performance improvement.

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유한요소 해석에 의한 공정변수가 인발 선재의 잔류응력에 미치는 영향평가 및 완화에 관한 연구 (A Study on the Influence of Process Parameters on Residual Stress and Reducing Residual Stress for Drawn Wire Using FE-Analysis)

  • 이상곤;황원호;김병민;배철민;이충열
    • 한국정밀공학회:학술대회논문집
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    • 한국정밀공학회 2005년도 추계학술대회 논문집
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    • pp.834-837
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    • 2005
  • This study presents a study on the influence of process parameters(semi-die angle, die reduction, friction condition, and bearing length) in drawn wire on residual stresses were investigated using FE-analysis. In this study, semi-die angle and die reduction have a significant effect on the residual stresses at the surface of drawn wire. In the previous study, in order to reduce the residual stresses, several methods were suggested: addition of axial tension, application of skin pass, straightening in multi-roll straightener etc. In this study, it can be known that the concurrent application of skin pass with low die reduction and low semi-die angle at the final stage of drawing operation reduces dramatically the both axial and hoop residual stresses after drawing.

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소방특별사법경찰제도의 효율적인 운용방안에 관한 연구 (Study on the Method for Effective Operation of Special Judicial Police System for Fire Service)

  • 조대근;황의홍;최돈묵
    • 한국화재소방학회논문지
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    • 제32권6호
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    • pp.100-107
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    • 2018
  • 현대사회의 다양화, 첨단화로 인하여 범죄의 내용도 전문화되면서 특별사법경찰제도의 역할은 중요하고 다양해지고 있다. 그럼에도 불구하고 수사업무를 수행하는 소방특별사법경찰은 대부분 화재조사 업무와 병행으로 인한 업무 과중, 인력 부족, 수사 전문성을 결여시키는 등의 문제점이 나타나고 있다. 본 연구는 소방사범 단속 수사사례를 통해 얻은 경험을 바탕으로 실제적인 문제점에 대한 개선방안으로 전보 제한 제도 개정, 정원 증원, 교육훈련 제도 개선, 전담부서 신설 등을 제시하고자 한다.

MECHA: 다중 스레드 및 효율적인 암호화 하드웨어 액세스 (MECHA: Multithreaded and Efficient Cryptographic Hardware Access)

  • 프라타마 데리;락스모노 아구스 마하르디카 아리 ;이크발 무함마드 ;김호원
    • 한국정보처리학회:학술대회논문집
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    • 한국정보처리학회 2023년도 춘계학술발표대회
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    • pp.339-341
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    • 2023
  • This paper presents a multithread and efficient cryptographic hardware access (MECHA) for efficient and fast cryptographic operations that eliminates the need for context switching. Utilizing a UNIX domain socket, MECHA manages multiple requests from multiple applications simultaneously, resulting in faster processing and improved efficiency. We comprise several key components, including the Server thread, Client thread, Transceiver thread, and a pair of Sender and Receiver queues. MECHA design is portable and can be used with any communication protocol, with experimental results demonstrating a 83% increase in the speed of concurrent cryptographic requests compared to conventional interface design. MECHA architecture has significant potential in the field of secure communication applications ranging from cloud computing to the IoT, offering a faster and more efficient solution for managing multiple cryptographic operation requests concurrently.

다중처리가 가능한 새로운 Globally Asynchronous, Locally Dynamic System 버스 구조 (A Novel Globally Asynchronous, Locally Dynamic System Bus Architecture Based on Multitasking Bus)

  • 최창원;신현출;위재경
    • 대한전자공학회논문지SD
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    • 제45권5호
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    • pp.71-81
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    • 2008
  • 본 논문에서는 새로운 On-Chip 버스로 다중처리 기반의 GALDS 버스 구조를 제안하였고 성능을 검증하였다. 제안된 GALDS 버스 구조는 멀티 마스터 멀티 슬레이브의 다중 처리를 지원하는 세그먼트(segment) 기반의 고성능의 양방향 다중처리 버스 구조(bi-direction multitasking bus architecture)이다. 또한, 시스템의 태스크(task) 분석에 의해서, 버스는 버스 동작 주파수의 배수 값을 갖는 주파수 사이에서 각각의 IP에 최적화된 동작 주파수를 선택하기 때문에 전체 전력 소모를 줄일 수 있다. 서로 다른 동작 주파수를 입력받은 IP들 간의 효율적인 데이터 통신을 위하여, 본 구조에서는 비동기 양방향 FIFO를 기반으로 하는 비동기 Wrapper 설계하였다. 또한, 버스 세그먼트의 추가만으로 시스템의 쉬운 확장이 가능하기 때문에, 제안된 구조는 IP 재사용 및 구조적 변경이 용이한 장점을 갖는다. 제안된 버스의 검증을 위해 4-마스터/4-슬레이브를 가지는 4-세그먼트의 버스와 비동기 Wrapper를 Verilog HDL을 이용하여 구현하였다. 버스의 다중처리동작 검증은 버스와 IP의 동작 주파수 비가 1:1, 1:2, 1:4, 1:8인 경우를 기준으로 시뮬레이션을 통해 마스터 IP에서 슬레이브 IP 사이의 데이터 읽기 및 쓰기 전송 동작을 확인하였다. 데이터 전송은 Advanced Microcontroller Bus Architecture(AMBA)과 호환 가능한 16 Burst Increment 모드로 하였다. 제한된 GALDS 버스의 최대 동작 지연시간은 쓰기 동작 시 22 클럭, 읽기 동작 시 44 클럭으로 확인되었다.

주방식 지하구조물의 최적 굴착공정에 대한 예비 분석 연구 (A preliminary study on the optimum excavation sequence of a room-and-pillar underground structure)

  • 이철호;최순욱;현영환;황제돈;장수호
    • 한국터널지하공간학회 논문집
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    • 제17권4호
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    • pp.499-511
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    • 2015
  • 주방식 지하구조물은 여러 개의 갱도 굴착에 의해 형성되는 격자 형태의 구조물이므로, 갱도들의 굴착순서에 따라 주방식 지하구조물의 시공성과 경제성이 좌우될 수 있다. 따라서 본 연구에서는 주방식 지하구조물의 지반조건, 굴착순서 등의 다양한 설계조건들을 고려하여 주방식 공법의 굴착공정을 검토하였다. 굴착공법으로는 발파공법을 가정하였으며, 가로 세로 병행 시공방식과 가로 세로 순차시공방식으로 구분하여 굴착공정을 검토하였다. 굴착순서에 따른 주방식 지하구조물의 안정성과 더불어 굴진면의 개수, 점보드릴의 이동거리 등에 따른 시공성을 분석한 결과, 구조적 안정성에는 큰 차이가 없으나 굴진면 운영 개소와 점보드릴의 이동거리 측면에서 가로 세로 병행 시공방법의 시공성이 상대적으로 유리한 것으로 나타났다.

Outcomes of Completion Lobectomy for Locoregional Recurrence after Sublobar Resection in Patients with Non-small Cell Lung Cancer

  • Cho Eun Lee;Jeonghee Yun;Yeong Jeong Jeon;Junghee Lee;Seong Yong Park;Jong Ho Cho;Hong Kwan Kim;Yong Soo Choi;Jhingook Kim;Young Mog Shim
    • Journal of Chest Surgery
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    • 제57권2호
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    • pp.128-135
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    • 2024
  • Background: This retrospective study aimed to determine the treatment patterns and the surgical and oncologic outcomes after completion lobectomy (CL) in patients with locoregionally recurrent stage I non-small cell lung cancer (NSCLC) who previously underwent sublobar resection. Methods: Data from 36 patients who initially underwent sublobar resection for clinical, pathological stage IA NSCLC and experienced locoregional recurrence between 2008 and 2016 were analyzed. Results: Thirty-six (3.6%) of 1,003 patients who underwent sublobar resection for NSCLC experienced locoregional recurrence. The patients' median age was 66.5 (range, 44-77) years at the initial operation, and 28 (77.8%) patients were men. Six (16.7%) patients underwent segmentectomy and 30 (83.3%) underwent wedge resection as the initial operation. The median follow-up from the initial operation was 56 (range, 9-150) months. Ten (27.8%) patients underwent CL, 22 (61.1%) underwent non-surgical treatments (chemotherapy, radiation, concurrent chemoradiation therapy), and 4 (11.1%) did not receive treatment or were lost to follow-up after recurrence. Patients who underwent CL experienced no significant complications or deaths. The median follow-up time after CL was 64.5 (range, 19-93) months. The 5-year overall survival (OS) and post-recurrence survival (PRS) were higher in the surgical group than in the non-surgical (p<0.001) and no-treatment groups (p<0.001). Conclusion: CL is a technically demanding but safe procedure for locoregionally recurrent stage I NSCLC after sublobar resection. Patients who underwent CL had better OS and PRS than patients who underwent non-surgical treatments or no treatments; however, a larger cohort study and long-term surveillance are necessary.

Acute Type A Aortic Dissection in a Patient with Situs Inversus Totalis

  • Kim, Dong Kyu;Lee, Ji Min;Heo, Seon Yeong;Jung, Jong Pil;Park, Chang Ryul;Lee, Yong Jik;Lee, Sang Cjeol;Hwang, Su Kyung;Kim, Gwan Sic
    • Journal of Chest Surgery
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    • 제53권5호
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    • pp.321-323
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    • 2020
  • We describe the occurrence of acute type A aortic dissection in a patient with situs inversus totalis. A 37-year-old man presented to the emergency department with acute chest pain. Initial chest X-ray findings showed a right-sided heart and a left-sided liver. Contrast-enhanced computed tomography revealed a Stanford type A acute aortic dissection, aortic root dilatation, and situs inversus totalis. All of the thoracic structures were mirror-image reversed and an abnormal coronary artery was observed. The Bentall operation was performed. This report demonstrates that computed tomography and echocardiography were useful for understanding the anatomy and the presence or absence of concurrent anomalies in a patient with situs inversus totalis. The patient's postoperative course was uneventful.

치매노인의 통증사정을 위한 한국어판 PACSLAC의 신뢰도, 타당도 및 유용성 평가 (Validity and Reliability of the Korean Version of the Pain Assessment Checklist for Seniors with Limited Ability to Communicate)

  • 김은경;김세영;엄미란;김현숙;이은표
    • 대한간호학회지
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    • 제44권4호
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    • pp.398-406
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    • 2014
  • Purpose: This study was done to develop and test the validity and reliability of the Korean version of the Pain Assessment Checklist for Seniors with Limited Ability to Communicate (PACSLAC-K) in assessing pain of elders with dementia living in long-term care facilities. Methods: The PACSLAC-K was developed through forward-backward translation techniques. Survey data were collected from 307 elders with dementia living in 5 long-term care facilities in Korea. Data were analyzed using descriptive statistics, Pearson correlation, Spearman's rho, paired t-test, ROC (receiver operation characteristic) curve with the SPSS/WIN (20.0) program. Results: The PACSLAC-K showed high internal consistency (.90), interrater reliability (.86), intrarater reliability (.93), and high concurrent validity (.74) in paired t-test with PAINAD. Discriminant validity also showed a significant difference compared with no pain. The PACSLAC-K showed a sensitivity of .93, specificity of .88, and Area Under the Curve of .95 in the ROC curve. Conclusion: The findings of this study demonstrate that PACSLAC-K is useful in assessing pain for elders with dementia living in long-term care facilities.

사립대학도서관의 직제 현황에 관한 연구 (A study on the current status of private university library's line and staff organization)

  • 김성수
    • 한국도서관정보학회지
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    • 제24권
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    • pp.301-334
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    • 1996
  • This study is aimed at examination and analysis of current status of university library's line and staff organization especially the private university's. Motivation for this study is based on the following facts : First, the library work now is changing from the conventional one to automated one. Second, librarians in the front line must be trained in the newly set work because of the separation of work process in automated libraries. Methodologies of this study, apart from theoretical aspects, were visiting and interviewing librarians at 30 university libraries, examining the current status and problems of the line and staff organization of the university libraries. The result from the study is as follows: First, interviewing reveals that 35% of the 75 private university library is having 'associate directorship by librarian' system. Benefits from this system are described, recommending other University libraries adopt this system. This system su n.0, pplements the weak point of concurrent director's office of lay professor, as well as encourages librarian's morale by promotion. Second, the current organization of the university libraries are to be reformed. Namely, 1) the name of each division must be newly and a n.0, ppropriately set of changed suiting for the work of automated library, thus reforming the division. This must be conducted via collection of opinions of the Korean Library and Information Science Society' and associated organizations. 2) Newly formed division(for example, administrative division or division of operation and management, division conducting digital library work, etc.) must be added to the line and staff organization. 3) For information service division, there must be a certain number of subject specialists. 4) Status of the directorship of university library, librarianship, issue of renaming of university library are also described.

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